Sheet feeding and stacking apparatus

ABSTRACT

An apparatus for feeding sheet-like articles along a path and selectively diverting them into one or the other of a plurality of bins where they are collected in stacked relation, comprises a series of pusher fingers spaced along an endless chain which is driven in synchronism with a source of supply of the articles so that the pusher fingers move in behind each article as it is fed to the stacker and pushes it until it is diverted into one of the bins. The drive for the pusher fingers is such that the fingers remain in substantially perpendicular relation to the plane of the article whether it is being diverted into a bin or is being moved along a horizontal path over one bin to the next, and the fingers are lifted from engagement with a diverted sheet as it enters a bin so as not to force the leading edge of the article against the side of the bin and damage it. To insure the article being dropped horizontally into a bin, rather than dropping in at an angle, means are provided in the bin for supporting the article in a horizontal position until the entire article is within the confines of the bin at which time the support means moves from beneath the article and allows it to drop down into the bin in a horizontal or flat condition. To aid in stacking the articles, one end portion thereof is provided with an aperture which drops down over an inclined spindle projecting upwardly from the bottom of the bin.

United States Patent Schieven et a1.

[ June 13,1972

[54] SHEET FEEDING AND STACKING APPARATUS [72] Inventors: Stanley R. Schieven, Webster; Gerald A.

Sampson, Penfield, both of NY.

[73] Assignee: Eastman Kodak Company, Rochester,

[22] Filed: June 1, 1970 [21] Appl. No.: 42,104

[52] U.S.Cl ..27l/64,214/8, 271/1, 271/68, 271/86 [51] Int. Cl. ..B65h 29/60, B65h 29/26, B65h 31/26 [58] Field of Search ..271/64, 68, 1, 86; 214/8 [56] References Cited UNITED STATES PATENTS 3,545,744 12/1970 Herman ..271/68 X 2,076,700 4/1937 Bryce ..271/64 X 2,300,863 11/1942 Bamford ..271/68 1,818,592 8/1931 Walworth ...2l4/8 X 3,419,266 12/1968 Martin ..271/86 FOREIGN PATENTS OR APPLICATIONS 1,254,670 l/l96l France ..271/64 Primary Examiner-Richard E. Aegerter Assistant Examiner-Bruce H. Stoner, Jr. AnomeyWilliam T. French and Robert F. Crocker [57] ABSTRACT An apparatus for feeding sheet-like articles along a path and selectively diverting them into one or the other of a plurality of bins where they are collected in stacked relation, comprises a series of pusher fingers spaced along an endless chain which is driven in synchronism with a source of supply of the articles so that the pusher fingers move in behind each article as it is fed to the stacker and pushes it until it is diverted into one of the bins. The drive for the pusher fingers is such that the fingers remain in substantially perpendicular relation to the plane of the article whether it is being diverted into a bin or is being moved along a horizontal path over one bin to the next, and the fingers are lifted from engagement with a diverted sheet as it enters a bin so as not to force the leading edge of the article against the side of the bin and damage it.

To insure the article being dropped horizontally into a bin, rather than dropping in at an angle, means are provided in the bin for supporting the article in a horizontal position until the entire article is within the confines of the bin at which time the support means moves from beneath the article and allows it to drop down into the bin in a horizontal or flat condition. To aid in stacking the articles, one end portion thereof is provided with an aperture which drops down over an inclined spindle projecting upwardly from thebottom of the bin.

12 Claims, 15 Drawing Figures PATENTEUJUN 13 I972 3, 669.448

sum 01 0F 10 FIG. IA

STANLEY H. SCH/EVEN GERALD A. SAMPSON INVENTORS AT TORNEYS 3N/ 7 dOHO PATENTEIJJuu 1 3 I972 SHEET 02 0F 10 STANLEY R. SCH/EVEN GERALD A. SAMPSON IN VENTORS Waflw ATTORNEYS PATENTEDJUH 1 3 I972- sum 03 ur 1o 71 STANLEY R. SCH/EVEN 4 GERALD A. SAMPSON INVENTORS HJddOHO -/0 Z V PATENTED HH1 1912 3. 669.448

sum as or 10 STANLEY R. SCH/EVEN GERALD A. SAMPSON INVENTORS WQ/M PATENTEUJUN 13 m2 sum as 0? 10 STANLEY R. SCH/EVEN GERALD A. SAMPSON INVENTORS WQAM A TTOR/VEYS PATENTEDJUN 13 m2 sum 07 or 1o $1 G w... mm

STANLEY R. SCH/EVEN GERALD A. SAMPSON INVENTORS A TTOR/VE V5 PATENTEUJUN13 I972 3, 669.448

sum 09 0F 10 STANLEY R. SCH/EVEN GERALD A SAMPSON IWENTORS ATTORNEYS PATENTEnJuu 13 1912 SHEET 10 0F 10 F/G'. l2

N w w M S STANLEY R.

GERALD A. SAMPSON INVENTORS A TTORNEYS SHEET FEEDING AND STACKIN G APPARATUS The present invention relates to an apparatus for feeding and stacking a series of sheet-like articles selectively into two or more groups spaced along a given path.

Machines for selectively stacking a series of sheet-like articles into two or more groups as they are moved along a path are generally well known. However, known apparatus of this general nature are limited to handling sheets which are more or less rigid and whose surfaces are not adversely afiected by pressure and abrasion because the feeding operation usually involves the surface of the article being subjected to the pressure of feed rollers, belts, etc.; the stacking operation depends upon the edge of the sheet striking the edge of a stacking bin or other abutment to stop its forward feeding motion as it reaches a given bin in which it is to be stacked; and the articles once stacked are shingled so that their surfaces are slid across one another similar to the manner in which playing cards are shuffled. Also, since known sheet feeding and stacking mechanisms more or less depend upon the sheet being propelled or dropped into the stack, they are useful primarily in handling sheets which are universally dense from one end to the other.

The primary object of the present invention is to provide an apparatus for feeding and stacking sheet-like articles selectively into two or more groups spaced along a given path which is adapted to handle sheet-like articles having edges which are more or less fragile, articles having surfaces which are sensitive to pressure and abrasion, as well as articles which are not universally dense throughout their length, without damaging the articles.

A further object is to provide a sheet-like article feeding and stacking mechanism of the type described wherein each article is positively conveyed along a given path by one or more pusher members which engage the. rear edge of the articles and positively move them along irrespective of whether they are moving along the main path or are being diverted to a given stacking bin. 7 I

Another object is to provide a sheet-like article feeding and stacking mechanism of the type set forth above wherein the drive means for the pusher members is-such that the pusher members positively engage and move the article upvuntil the time the trailingedge of the article passes over-the trailing edge of the stacking bin to which it is diverted, at'which time the pusher members disengage the article so that its forward edge is not driven against the leading edge of the bin or any other stationary object as the result of which its edge might be damaged. I

A further object is to provide a feeding and stacking mechanism of the type described wherein the pusher members are fingers extending vertically downward from an endless chain and means are provided 'to orient the fingers as they move along so that they will be maintained in substantially perpendicular relation to the article engaged thereby whether it is moving along a horizontal path or is being diverted therefrom into a stacking bin. I

' Still another object is to provide a feeding and stacking mechanism of the type described wherein each article is supported in a horizontal position near the top of the stacking bin until it is conveyed completely within the bin and after which it is released to drop flatwise' to the bottom of the bin or onto a stack of articles already deposited therein.

Another object is to provide a feeding and stacking mechanism of the type described which is designed to handle a sheet-like article one end of which is flimsy and limp and is tion and its methods of operation, together with additional objects and advantages thereof, will best be understood from the following description of specific embodiments when read in connection with the accompanying drawings in which:

FIGS. 1A and 18, when placed end to end with broken line A at the left of FIG. 1B superposed with the broken line A at the right of FIG. 1A, is a top plan view of the complete feeder and stacker constructed in accordance with a preferred embodiment of the present invention;

FIGS. 2A and 28, when joined end to end at broken line B. is a front elevation, partly in section, of the feeder and stacker shown in FIGS. 1A and 1B; 1

FIG. 3 is an enlarged front elevation, partly in section, of the front part of the stacker, including the first stacking bin;

FIG. 4 is a plan view of the sheet-like .article which the present feeder and stackeris adapted to handle;

FIG. 5 is a schematic view showing the path of movement of the endless chain carrying the pusher fingers;

FIG; 6 is a vertical sectional view taken substantially on line 6-6 of FIG. 2A;

FIG. 7 is an enlarged elevational detail, partly in section, showing the construction of the pusher members and how they cooperate with grooves in one of the supporting plates of the stacker to extend below the plane of the article being engaged;

FIG.- 8 is an enlarged front elevational detail showing how the chain path control sprockets cooperate with thechain to move it throughan'S curve at the beginning of ,each stacking station; g

FIG. 9 is an enlarged sectional detail taken through one of the first two stacking stations to show the shape of the stacking bin and the position it assumes relative to the feeding path of the stacker;

FIG. 10 is an enlarged schematic plan view of one of the first stacking stations, and illustrating how an article advances into the stacking bin and mounted therein; 1

FIG. 11 is a front view corresponding to FIG. 10 and showing the shape of the helicopter blade and'its position relative to the stacking bin; v FIG. 12 is an enlarged plan detail showing another embodiment of the stacking bins; and

FIG. 13 is a front view corresponding substantially to FIG. 12 but showing the article collecting blades 100 and 10] movedtotheirinoperative position. v

A preferred embodiment of the present invention is designed to stack sheet-like articles 10 of the type shown in FIG. 4. This article comprises a generally-rectangular portion 1 1 having a tapered end from which extends an elongated pull tab 12 having an aperture 13 therein. The portion 11 of the article may consist'of a-fairly rigid sheet of paper or the like,

. whereas the pull tab 12 attached thereto is made of a material provided with an aperture. In order to properly stack this arti- 1 cle the stacking bin isprovided with an upstanding spindle which passes through the aperture in the part as it is dropped into the bin. The spindle is inclined from the vertical so that as the article falls it will be cammed in the direction of the limp end.

The novel features which we consider characteristic of our invention are set forth with particularity in the appended claims. The invention itself, however, both as to its organizawhich is-rather flimsy and limp, particularly as compared to the remainder of the article. Since the density of the article va- I ries along its length, it will be appreciated that the problem of feeding such articles along a path and selectively stacking them in bins spaced along such path presents a unique problem not readilysolved by conventional typesof sheet stacking mechanisms. This is particularly true when'it is realized that'this stacking device must be capable of operation in conjunction with a continuous machine which produces and v feeds such articles to the stacker at a high rate of speed.

Briefly, the present stacking apparatus comprises a plurality of spaced, stationary flat surfaces which define a horizontal path .onto the leading end of whichthe articles to be stacked are fed in spaced apart relation. The source of supply of the articles is immaterial, but in one instance it may be a chopper which is continuously chopping a continuous strip of material into individual pieces of the shape shown in FIG-4 which are fed from the chopper to the stacker surface by a belt conveyor which is overdriven to produce spaces between successive articles.

As the parts are fed to the stacker in spaced apart relation, pusher fingers spaced along an endless chain are brought from is controlled by a helicopter blade above into the spaces between the articles. The stacker is driven syncronously with the chopper, or other sources of article supply, so that each finger or set of fingers enters just behind the trailing edge of a part. Each article is pushed by those fingers along a stationary and essentially flat surface to the desired stacking point. Grooves are provided in this flat surface so that the fingers will project below the bottom plane of the article and thus be certain to push it as desired.

There are at least four stacking stations spaced apart along and beneath the conveyor, the first two being used to alternately collect and stack good product, the third being used to randomly collect product for quality control, and the fourth being used to collect rejects, or all product passing the first three stations. Ahead of each of the first three stacking positions a support for the product is provided by a diverter which is situated between the spaced apart stationary flat surfaces. These diverters are pivotal between an upper inoperative position and a lowered operative position. In the upper position the diverters form a horizontal surface continuous with the stationary flat surfaces ahead and behind them. In the lowered position they form a ramp with a slight downward slope to direct an article into a stacking bin located at one of the stacking stations. If a diverter is in its upper position, the product is to be carried past its associated stacking station to one of those following. Proper timing and quick actuation of the diverters insure that each diverter changes positions between successive articles.

A sheet which is to be stacked should be positively conveyed until the trailing edge of the sheet clears the trailing edge of a desired stacking bin, but not beyond this point. If the position conveyance of a sheet stops too soon, the stacker will not be reliable, particularly at slow speeds, and if it is continued too long the sheet will be damaged as its edge hits the lead end of the bin. As mentioned above, the product being conveyed will be on either one of two paths; either downward at a slight slope to be stacked, or horizontal to be carried past a stacking station. The pushing fingers provide the positive conveyance when it is wanted on either of these two paths. This is accomplished by lifting the fingers just as the trailing edge of the piece passes the trailing end of the stacking bin. The fingers are lifted just far enough to pass above a piece to be stacked, but not far enough to lose contact with a piece which is being moved past a stacking station. This controlled lifting takes place as each set of pushing fingers comes to the trailing edge of a stacking bin whether the piece it is pushing is to be stacked or not.

The pushing fingers are made of suitably thin material and are formed and mounted on the endless chain so as to act as substantially positive pushers. However, should any resistance to pushing a piece occur, the fingers will deflect and thus ride over the jammed piece without damage to the fingers. The lowering and raising of the pusher fingers relative to the article they are pushing as they approach and reach a stacking station is produced by the shape of the path of the endless chain to which they are attached. The fingers are oriented so as to remain substantially perpendicular to the sheet they engage regardless of which of the two paths they take by pivotally mounting the fingers on the chain and having a follower arm connected with each set of fingers engage a suitably shaped cam extending along the horizontal path of the conveyor.

At each stacking station the articles are stacked in a removable bin which when filled can bereplaced with an empty bin. It is for this reason that at least two stacking stations for good product is provided, namely to allow the use of one station while the loaded bin in the other station is being removed and replaced by an empty one. Extending upwardly from the bottom of each stacking bin there is a spindle which extends through the aperture in each article as it drops into the bin. Proper stacking requires that this spindle on which the parts are stacked must not be vertical. It is preferably inclined about 35 from the vertical so that as the part falls into the bin it must move toward the end with the aperture.

To insure that the parts are dropped horizontally into the stacking bins a rotating blade is mounted at each of the first three stacking positions on a shaft with a vertical center line just beyond the leading edge of the stacking bin. This blade is a disc cut away in two regionssymmetrically about the axis and rotates for each product pitch. It is bent to provide the following features: Each blade section forms a substantially horizontal support surface fora part which is to be stacked; the lead edge of each part is supported on this surface from the time it enters the stacking bin until its trailing edge enters the bin. Just as the trailing edge comes over the stacking bin and the pushing fingers disengage from the part, the trailing edge of the horizontal support surface of the blade rotates from under the leading edge of the part allowing the part to fall horizontally into the bin. A portion of each blade section is bent so that it forms a descending spiral beneath which the part falls and which, in effect, pushes the part down into the bin to get it out of the way should it not fall clear of the next part entering the bin.

Good product is stacked alternately in groups at the first two stacking stations. Samples randomly selected for quality control are stacked in the third station. Since only a few sam-- ples need be collected at any one time, a shallow bin may be used at the third station because the distance of fall of the articles is slight. The fourth station is for rejects, and since damage to rejects is acceptable, neither aspindle nor a rotating blade is required in the fourth station. Since all "product which passes the first three sections is destined for the reject bin, no diverter is provided here either.

While a stacking apparatus according to the present invention could be made to handle sheet-like articles of any shape and fed to it in spaced relation by different means from any source, for purposes of illustration, a preferred embodiment thereof has been shown which stacks sheet-like articles of the type shown in FIG. 4 and which are continuously chopped at a fixed rate from a continuous strip of material. The sheet-like articles, as mentioned above, comprise a rectangular portion 11 which is fairly rigid and to one end of which is attached an elongated pull tab 12 made of rather flimsy and limp material having an aperture 13 therein. Referring now to the drawings,

and particularly FIGS. IA, 13, 2A and 28 thereof, the parts 10 to be stacked emanate at a fixed rate from a continuous chopper, only a part of which is shown at C, but whose center line and chop line are designated by legends at the left hand side of the drawings.

The lead edge of each rectangular part 11 of article 10 is caught in the nip 14 of a short belt section 15 as that part is being chopped. The short belt section comprises an upper belt 16 passing around four spaced guide rollers l7, l8, l9 and 20 mounted on shafts extending from a vertical supporting wall 21 at the rear side of the machine, and a like lower belt 16' passing around four spaced guide rollers l7, 18, 19', and 20' mounted on shafts also extending from vertical wall 21. The reaches of the two belts extending between guide rolls l7, l8 and between 17' and 18 engage one another and serve to grip and convey the articles from the chopper to the stacking apparatus. Each set of belts is driven at the same speed by suitable means at a rate faster than the continuous strip is fed to the chopper to produce a space between successive articles. While each set of belts may be driven by any suitable means, for purposes of illustration, the drive for the upper belt is shown as comprising a gear 22 fixed to the shaft of roller 20 which will be fixed to its shaft rather than being rotatable thereon. The lower belt 16 may be driven in the same, but not shown, manner by fixing roller 20 to its shaft and fixing a drive gear thereto. Looking at FIG. 1A, it will be seen that the belt section engages only the rectangular and substantiallyrigid part 11 of the article for feeding the same from the chopper to the stacker. The flimsy pull tab portion 12 of the article is supported on four spaced wires or rods 23 which lie in the plane of the superposed regions of the belts l6 and 16 and offer a minimum amount of drag to this part of the article as it is being fed to the stacker. 1

At the exit end of the belt section, pushing fingers 24 spaced along an endless chain 25, and fonning a part of the stacker, are brought from above into the spaces between successive articles being fed to the stacker by the belt section. The stacker is driven syncronously with the chopper so that each set of pusher fingers 24, which are mounted to the chain in pairs spaced transversely of the article as shown in FIG. 6, enters just back of the trailing edge of the rectangular portion 11 of an article 10. The articles are pushed by these fingers 24 along an essentially horizontal path to the desired stacking station. Spaced along this horizontal path are two stacking stations 26 and 27 into which good product may be alternately stacked, a sample station 28 where a random sampling of articles may be stacked for quality control purposes and a reject station 29 where all articles passing the other stations are collected. The horizontal path for the articles moving through the stacker comprises three stationary horizontal tables 30, 31 and 32 spaced along the length of the stacker and three article diverters 33, 34 and 35, one located in the space between each of the stationary tables. As will be fully described below, these diverters move between an upper or inoperative position, see diverter 34 in FIG. 2B, in which they are horizontal and lie in the plane of, and substantially fill the space between the stationary tables, and a lowered or operative position, see diverter 33 in FIG. 2A, wherein they are inclined downwardly to direct an article to one of the first three stacking stations. Longitudinal grooves 37 are provided in the top of the stationary tables and diverters so that the pusher fingers will project below the bottom plane of the article and thus be certain to positively engage the rear edge thereof and push it as desired whether it is being diverted to a stacking bin or not, see FIGS. 2A, 2B and 6.

Since each of the three diverters 33, 34 and 35 are exactly alike and are operated by the same type of mechanism to be moved between their operative and inoperative positions, only one of them will be described in detail. Looking at the first diverter 33 shown in FIGS. 1A, 2A, it has a first section 38 nearer the vertical supporting wall 21 which is provided with grooves 37 and supports the rectangular portion 11 of the article 10, and a second section 39 adjacent to, and substantially coplanar with section 38, which is adapted to support the pull tab portion 12 of an article. The top of the second section 39 is provided with four longitudinal raised ribs 40 which support the pull tab portion 12 of the article 10 at limited spaced areas to reduce the area of contact on this part of the article as it is pushed along the diverter. In other words, these raised ribs serve the same purpose as rods 23 at the short belt section of the stacker. For preventing air currents from accidentally raising the flimsy pull tabs as they are moved along the diverters, the forward edge of each diverter is provided with a hold down member 41 hinged at 42 to the front edge of the diverter. This hold down member 41 should not press directly on top of the pull tab but is merely provided to confine the pull tab to move flatwise along the diverter. As best shown in FIGS. 2A and 2B, the leading end of the hold down member is provided with an upturned end 43 for directing the pull tab portion 12 under the hold down member and also to serve as a finger piece for lifting the hold down member for any reason. The rear edge of each diverter is provided with a vertical guide member 44 which engages the transverse edge of the rectangular portion 11 of an article to guide it properly into the stacking bin associated with the diverter, see FIGS. 1A and 1B. The edge of this vertical guide member first approached by an article is bent rearwardly, as best shown in FIGS. 1A and 13, to ensure that the rectangular portion of the article will be guided properly by guide member 44 and not be hung up on the leading edge thereof.

Each diverter, see diverter 33 in particular, is anchored at one end to a shaft 46 extending transversely of the stacker and rotatably mounted in vertical supporting plates 21, 49 and 49 spaced apart transversely of the feeding path of the stacker. This shaft 46 is rocked by a suitable mechanism, eg a solenoid or hydraulic cylinder 47 acting through a suitable linkage 48, to move the diverter 33 between its operative and inoperative positions at a programmed time. For example, if the capacity of each of the first two stacking bins 26 and 27 is 250 articles, and it is desired to randomly collect every 50th article in bin 28 for sampling purposes, then the diverters will be programmed so that the diverter 35 in front of stacking bin 28 will be moved to its operative position once in the feeding of every 50 articles and the second diverter 34 will be held in its inoperative position while the first diverter is moved to and held in its operative position for the first 49 articles, moved to its inoperative position for the 50th article, and again moved to its operative position for the next '49 articles, moved to its inoperative position for the 50th article, and again moved to its operative position for the next 49 articles, etc. until first bin 26 is filled. At this time, the first diverter 33 will be moved to its inoperative position and second diverter 34 will be moved to its operative position to collect all but every 50th article until bin 27 is filled. While one of the first two bins 26 or 27 is filling, the other is being emptied or replaced with an empty receptacle. All articles not collected in bins 26, 27 or 28 will be pushed into reject bin 29 at the end of the stacker path. Articles may be rejected for any number of reasons, a major one being that the article includes a splice made in the continuous web fed into the chopper, and the approach of a reject to or through the stacker may be detected by any suitable means, not shown, which will in turn feed the information into a memory device associated with the stacker programmer so that when the article to be rejected reaches the stacker, all three diverters will be moved to their inoperative position and pass that article to the reject bin.

The drive for the pusher fingers 24 comprises a pair of endless linked roller chains 50 mounted in parallel spaced relation and engaging two double sprockets 51, one of which may be driven by any suitable means, see FIG. 1B. As schematically shown in FIG. 5, the pusher fingers 24 are pivotally mounted in spaced relation along the chains 50 so as to move in behind the tailing edge of successive articles fed to the stacker. As will be described in more detail below, these pusher fingers are so mounted on the chain, and the chain is so guided, that in the feeding reach of the chains, the fingers extend vertically downward and will at all times extend below the plane of the article being pushed, whether the article is being diverted into a stacking bin or is being moved in a horizontal plane across the given stacking bin. Also the fingers are lifted as they approach each stacking bin so that they will disengage an article being diverted into a given bin just as the trailing edge of the article passes the trailing edge of the bin so as not to force the part against the leading edge of the bin and damage its edge. The fingers while moving along the feeding reach of the stacker are continually oriented so that they remain substantially perpendicular to the edge of the article being pushed regardless of whether it is being diverted to a stacking bin or not. As the fingers 24 move along the return reach of the chains 50, they project vertically upward, as shown in FIG. 5. In other words, the pusher fingers extend substantially at right angles to, and away from, the chains at all times.

Referring now particularly to FIGS. 6, 7 and 8, the guiding and mounting means for the chains and the pusher fingers will be described more in detail. The guiding and mounting means for the chains comprises the vertical supporting plates 21 and 49 which serve as front and rear chain mounting plates respectively, held in spaced relation by a spacer tube 54 and in which mounting plates double sprockets 51 are rotatably mounted. The return reach of the chain is supported by straight, horizontal return rails 55 carried by a support bracket 56 bolted, or otherwise fastened, to a supporting plate.57 welded, or otherwise, fastened, to and extending from the rear chain mounting plate 49. The rollers 50' of the chains 50 ride on the top of these support rails.

The chain path of the forward or feeding reach of the chains 50 is controlled by a series of spaced stationary rails and three pairs of chain path control sprockets which the rollers of the chain engage as they move along. Referring now to FIGS. 2A, 2B and 5, in advance of each of the stacking bins 26, 27, and 28 there is a vertical stationary rail 59 on whose top surface 60 ride rollers 50 of the chains. This top surface 60 is inclined downwardly so as to be substantially parallel to its associated diverter when it is in its downwardly inclined or operative position. This means that when a pushing finger is approaching any one of the three diverters 33, 34 or 35, they will drop down enough to keep the ends thereof below the plane of the article and maintain a positive pushing control of the article up to the time it reaches the associated stacking bin. Since the angle of tilt of the diverters when in their operative position is rather slight, this downward movement of the fingers when the diverters are in the horizontal or inoperative position can be accommodated by making the depth of the grooves 37 in the diverters equal 'to, or slightly greater than, the downward movement of the fingers.

At each of the first three stacking points the chains 50 follow an S curve upward to a higher level as prescribed by a pair of idler sprockets 160, see FIG. 8. These idler sprockets 160 have shorter teeth than normal and are mounted with the teeth not meshing in order to confine the rollers 50 of the chains. The resulting upward motion of the chain lifts the pushing fingers 24 from engagement with a diverted article at the instant the trailing end of the article passes over the trailing wall of the associated stacking bin so that the leading end of the article will not be forced against the leading wall of the bin and be damaged.

The manner in which the pushing fingers 24 are mounted on the chain and are properly oriented as they move along the feeding reach of the chain will now be described. Referring particularly to FIGS. 6, 7 and 8, the fingers 24 are fastened to a 'pivotable rod 61 rotatably mounted through the rollers 50 connecting the links of the chains 50. While the pusher fingers 24 may be made of any suitable material and be fastened to the roll rod 61 in any number of ways, as clearly shown in FIG. 7, we have shown these fingers made of plastic and being substantially U shaped with the arms of the U connected by an arcuate strap portion 62. One arm of the U constitutes finger 24 proper while the other arm 63 of the U cooperates with the finger to fasten the finger to a rectangular block 64 which in turn is fixed to the rod 61 in any suitable manner, e.g. by a set screw not shown. When the plastic finger is molded, the arcuate strap portion is stressed so as to normally force the two arms of the U together. Consequently, the fingers can be readily mounted on the block 64 by sliding the two arms of the U down over opposite walls of the block and such mounting prevents the fingers from rotating relative to the block 64 and hence the rod 61. Integral with the block 64 and extending downwardly from the rear thereof are a pair of spaced holddown fingers 65 which ride lightly on the top of the stationary tables 30, 31, 32 or the diverters 33, 34 and 35 to'hold the leading end of a succeeding article onto the surface thereof to overcome any tendency for that article to lift.

As mentioned above, it is desirable that the pusher fingers 24 be continuously oriented to maintain the article engaging edge thereof substantially perpendicular to the rear edge of the article engaged thereby. Whether the article is being pushed along the horizontal path or a diverted path. To accomplish this, a follower ann 66 is attached to each rod 61 or block 64 to extend rearwardly and downwardly therefrom. The follow arm'66, the rod 61 and the pusher finger rotate about the rod centerline together. A roller follower 67 rides in a cam track 68 fonned in the front face of the front mounting plate 52, see FIG. 6. As clearly shown in FIGS. 3, and 8, this cam track 68 follows a path 68 which is below and roughly parallel to the chain path. The result is that the properly shaped cam path 68 causes the fingers to maintain the proper rotational orientation relative to the article it is pushing at all points in their travel through the feeding reach of the stacker chain 50. That portion of the cam track 68 in the return reach of chain 50 is straight and holds the fingers vertically upward in this portion of their travel, see FIG. 5.

In the present instance, the articles described are to be collected at the first two stacking stations in specially shaped bins or boxes which can be removed from the stacker when filled and which can be replaced with an empty bin when one is filled. To this end, the articles are collected in boxes 70 which are relatively deep and have a spindle 71 extending upwardly from the bottom thereof and over which the aperture 13 in the pull tab 12 of the article 10 passes as it is dropped into the box, see FIG. 9. These boxes 70 may be automatically fed into position on a suitable conveyor mechanism shown in FIG. 2A as comprising a platform 72 moved in a direction out of the plane of the paper by a sprocket drive 73 to the proper position and then lifted into the receiving position shown in FIG. 9, or the boxes may be manually inserted into and removed from position in the stacker. Regardless of how the collecting boxes are positioned in the stacker, the important thing is that they be inclined as shown in FIG. 9 because proper stacking of the article in question requires that the spindle 71 on which the parts are stacked must not be vertical. The spindle 71 is inclined about 35 from the vertical so that as the article slides down the spindle it must move farther toward the end with the aperture 13. The use of an inclined spindle provides for a controlled fall of an article such as disclosed and which is of unequal density throughout its length and very limp in the cross machine dimension. Looking at FIG. 2A, it will be seen that when the box 70 is in receiving position, it is moved up snugly between spaced vertical walls 74 and 75 fixed to the frame of the stacker so that walls 74 and 75 along with the box constitute a stacking bin into whicharticles are diverted. As the pull tab portion of the part passes into the bin and over the spindle 71 it is cammed downwardly by a stationary member 76 fixed to the underside of the stationary table 30 or 31 (depending upon which stacking bin is involved). This stationary member is provided to aid in directing the aperture 13 in the pull tab portion onto the spindle.

Because of the unequal density of the article involved here, and the long fall which the articles are subject to in each of the first two stacking bins, it has been found desirable, if not necessary, to provide a means for insuring that they fall into the bins flat-wise, or horizontally, rather that at an angle. To this end, each of thethree stacking positions includes an article-positioning mechanism which is about to be described in conjunction with only the first stacking station 26 since like mechanisms will be used at each of the stations. Looking at FIGS. 1A, 10 and 11, a rotating blade 80 is mounted on a shaft 81 with a vertical centerline just past the leading edge of each of the first three stacking bins. This blade, which we have chosen to refer to as a helicopter blade for better definition, is a disc cut away in two regions 82 symmetrical about its axis to break the blade into two blade sections 79 and 79'. A drive including shaft 182 and a coupling 183 between shafts 81 and 182 rotates the blade 180 clockwise for each article pitch, see

FIG. 3. The leading end of each blade section is bent, as indicated at lines 84 and 84', FIG. 10, to provide the following features: the trailing end of each blade section forms a substantially horizontal support surface 85, 85 for the rectangular portion 11 of an article 10 to be stacked, and the lead edge of an article is supported on this surface from the time it enters the stacking bin until the trailing edge of the article enters the bin. This is shown schematically in FIG. 10 where a succession of broken lines show the progress of the leading edge of an article 10 as it is diverted into the stacking bin 26 and finally reaches a position directly above the stacking bin, as shown by a complete broken outline of the article. In this FIG. the helicopter blade is shown in the position where the trailing edge 86 of section 85 which supported the sheet until it moved into position above the bin is in line with the trailing end of the bin and the article is about to be dropped into the bin. During this time the leading turned up end of the next blade section 79 has been moving over the top of the article just dropped by blade section 85 to separate it from the next article moving into the bin. At the same time the horizontal supporting surface 85' of blade section 79' is moving into the path of the next article to support it until it moves into alignment with the bin and at which time it drops it into the bin. Thus for each rotation of the helicopter blade two sheets are dropped into the bin in a horizontal position. It should again be pointed out that the pushing fingers 24 are lifted and disengaged from the advancing article at the same instant that the trailing edge of the article passes over the trailing edge of the bin and the helicopter drops that article. The leading end of each blade section 79, 79' is bent upwardly along line 84, 84 so that it forms in effect a descending spiral beneath which the part must fall. It will be noticed (see FIG. 10) that on top of the leading wall 74 of each of the first three stacking bins there is positioned a horizontal plate 87 having a shape substantially the reverse of that of the part 11 on the article, or one that narrows the opening of the leading edge of the stacking bin and forms a shape which corresponds with the taper and pull tab portions of the articles to be stacked. This plate 87 aids in the proper positioning of the article above the bin opening for the reason that it supports the pull tab portion 12 and the tapered portion of the article until the trailing straight edge of the article passes over the leading edge 74 of the bin.

If the pull tab 12 of the article is made of a very limp material it has been found that it is difficult to properly direct the aperture 13 therein onto the spindle 71 because the pull tab tends to drop down from the horizontal prematurely. It has been found that this problem can be overcome by mounting a second helicopter blade 88 forward of the first helicopter blade 80 to horizontally support the pull tab portion 12 of the article 10 until the article is completely over the bin, see FIG. 12 and 13. This second helicopter blade can be essentially the same construction as helicopter blade 80 already described and differs therefrom primarily in that it is smaller in diameter. It is mounted on a vertical shaft 89 located substantially in the center of the bin with respect to the direction of feed of the article, and comprises two blade sections 90 and 90' which are similar both structurally and functionally with blade section 79 and 79 of helicopter blade 80. This second helicopter blade 88 must be driven in synchronism with the first helicopter blade 80 so that it will drop the pull tab portion of an article at the same time the helicopter blade 80 is dropping the rectangular portion 1 lof the article. To this end the lower end of the vertical shaft 89 is shown provided with a pulley 91 which is connected by a belt 92 to another pulley 93 which is in turn driven from the first helicopter blade 80 by a belt 94 engaging a pulley 95 on the vertical shaft 81 and another pulley, not shown, coaxial with and fixed to rotate with pulley 93.

Sometimes it has been found difficult to consistently drop the articles into the bins so that the aperture 13 in the pull tab accurately engages the spindle 71 so as to slide down it freely. It has been found that this problem can be helped if instead of dropping the articles onto the spindle one at a time, a group of say five or ten of them is collected above the spindle and then dropped onto the spindle as a group. To this end, means may be provided below the helicopter blades 80 and 88 for collecting a stack of five or ten articles and then dropping them as a group into the bin and onto the spindle. As shown in FIGS. 12 and 13 such a collecting means may comprise a pair of blades 100 and 101 extending through the leading and trailing walls, respectively, of the bin. Each of these blades is connected to the plunger 102 of a quick-acting solenoid or pneumatic cylinder 103 to reciprocate from an operative position shown in FIG. 12, wherein they project slightly into the bin to support a group of articles dropped down into the bin, and an inoperative position, shown in FIG. 13, wherein they are withdrawn from the bin to allow a collected group of articles thereon to drop down into the bin. The actuating means for these blades will be programmed so that they will remain in their operative position for a time sufficient to collect a given number of articles and then be withdrawn quickly to drop the collected group. It will be appreciated that the actuating means for these collecting blades must act quickly in order to return ten to their operative position after they have been moved to their inoperative position in order for them to be in a position to support the succeeding article dropped into the bin.

Referring to FIG. 28, since random samples are collected in the third stacking station 28, and only a few samples need be collected at one time, a shallow removable bin 105 is all that is required at this station. Also, since the distance of fall is slight in this shallow bin no spindle is needed in the sample stacking station. It might also be mentioned at this point that if the number of pieces to be collected at the first two stacking stations at one time is small, e.g. 50 60 pieces, then shallow bins or boxes could be used instead of relatively deep ones as shown. If shallow boxes are used, then an inclined spindle may not be required therein to aid in the stacking of the pieces in the box because of the shorter distance the pieces have to fall. Should it be found desirable to collect the pieces on a spindle for purposes of ready retrieval or storage, then in shallow boxes or bins a vertical, rather than an inclined, spindle may be used.

As mentioned above, the fourth station 29 is for rejects, and since damage to reject products is acceptable, neither a spindle nor a rotating blade is required at this station. Since all product which passes the first three stations is destined for the reject bin, no diverter is provided here either.

The invention has been described in detail with particular reference to preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.

We claim:

1. Apparatus for stacking a series of sheet-like articles selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation comprising in combination,

I. two or more stacking bins spaced apart along, and

located below, said path to receive said articles;

2. support means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path;

b. a diverter located ahead of each stacking bin and in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two adjacent tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto;

c. means for selectively moving each of said diverters between their inoperative and operative positions;

3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative positions and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position, and including a. a plurality of pusher fingers;

b. means for moving said pusher fingers in succession behind, and in substantially perpendicular relation to, the trailing edge of successive articles as they enter said path and moving them along said path to push the article across said support means; and

c. means for successively lowering and raising said pusher fingers relative to the article engaged thereby as they approach and reach, respectively, a stacking bin to maintain said pusher fingers in pushing engagement with said article up to the time it is deposited in said stacking bin or is moved along said path across said stacking bin.

2. Stacking apparatus as defined in claim 1, wherein said means for moving said pusher fingers comprises a driven endless conveyor one reach of which is above and substantially parallel to said path and moves in an article-feeding direction relative to said path; means for maintaining said pusher fingers in spaced relation along said conveyor so that as said pusher fingers enter and pass along said one reach of the endless conveyor successive ones thereof move in succession in behind the trailing edge of successive articles as they enter said path and push the articles along said path, and wherein said means for successively lowering and raising said pusher fingers comprises guide means in said one reach of the conveyor for directing that portion of the conveyor approaching a stacking bin downward in a direction substantially parallel to the diverter when in its operative position and quickly raising said conveyor at the point in said one reach where a pushing finger reaches the trailing edge of a stacking bin.

3. Stacking apparatus as defined in claim 2, wherein said means for mounting said pusher fingers along said conveyor comprises a plurality of rods rotatably mounted at spaced points along said conveyor with their axis extending transversely of and substantially parallel to said path, one or more of said pusher fingers fixed to each rod to extend substantially at right angles to the axis thereof, a cam follower fixed to and extending at right angles from each of said rods, and an endless stationary cam path substantially concentric to said endless conveyor and engaged by a portion of said cam follower to rotatably position said rods so that the pusher fingers connected thereto remain at substantially right angles to, and project away from, the conveyor throughout the path of travel of said conveyor, that portion of said cam path controlling the pivotal movement of said rods as they move along said one reach of the conveyor so shaped that it maintains said pusher fingers substantially perpendicular to an article engaged thereby as the pusher fingers move up and down relative to an engaged article as dictated by said guide means for the conveyor.

4. A stacking apparatus as defined in claim 3, including article hold-down means connected with said rods for engaging the top of an article to hold it down as it is being pushed along said path by said fingers.

5. A stacking apparatus as defined in claim 1, including an article-supporting member associated with at least one of said stacking bins and movable in synchronism with the movement of said pusher fingers between an operative position, wherein it will provide a substantially horizontal support for an article fed into said bin from the time the leading edge of the article enters the bin and engages said article supporting member until the trailing edge of the article enters the bin, and an inoperative position, wherein it moves from beneath an article fed into the bin and supported thereby to allow the article to drop down into the bin in a substantially horizontal condition.

6. A stacking apparatus as defined in claim 1, wherein said article-supporting means comprises a disc rotatable about a vertical axis beyond the leading edge of the bin it is associated with and in a plane immediately below the path of entrance of an article entering said bin, said disc cut away to provide at least one arcuate horizontal support surface for an article entering said bin from the time it enters the bin and until its trailing edge enters the bin and at which time it passes from beneath the article to allow it to drop into the bin.

7. Apparatus for stacking a series of sheet-like articles selectively into two or more groups spaced along a given path to and over which the articles are fed in spacedapart relation comprising in combination,

1. two or more stacking bins spaced apart along, and

located below, said path to receive said articles;

2. support means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path;

b. a diverter located ahead of each stacking bin in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two spaced tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto;

c. means for selectively moving each of said diverters between their inoperative and operative positions;

3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative position and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position; and

4. article-supporting means associated with at least one of said stacking bins and movable in synchronism with the article moving means between an operative position, wherein it will horizontally support an article fed into said bin from the time the leading edge of the article enters the bin until the trailing edge enters the bin, and an inoperative position, wherein it moves from beneath an article fed into the bin to allow the article to drop down into the bin in a substantially horizontal condition; said last mentioned means comprising a plurality of blades symmetrically arranged to rotate about a vertical axis beyond the leading edge of the associated bin and in a plane immediately below the path of an article entering said bin, each of said blades providing an arcuate, substantially horizontal support surface for an article entering said bin from the time it enters the bin and until its trailing edge enters the bin at which time it passes from beneath the article to allow it to drop into the bin.

8. A stacking apparatus as defined in claim 7 in which the leading portion of each blade is bent to form a descending spiral beneath which the article freed from the preceding blade must fall.

9. A stacking apparatus as defined in claim 7, wherein said sheet-like articles to be stacked vary in density lengthwise thereof and include an end portion which is quite'limp in the lengthwise direction and is not supported by said article-supporting means; and including an end portion supporting means movable between an operative position, wherein it will horizontally support the end portion of an article fed into said bin from the time the leading end thereof enters the bin until the trailing edge enters the bin, and an inoperative position, wherein it moves from beneath the end portion of an article fed into the bin to allow it to drop into the bin in a substantially horizontal condition; and means for moving said end portion supporting means between its operative and inoperative positions in synchronism with the movement of said article supporting means between its operative and inoperative positions so that said end portion will be supported in substantially the same plane as the remainder of the article as the article is fed into a bin and will be released at the same time as the remainder of the article is released by said article-supporting means to cause the entire article to drop down into the bin in a substantially. horizontal condition.

10. Apparatus for stacking a series of sheet-like articles selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation, said sheet-like articles varying in density lengthwise thereof and including an end portion which is quite limp in the lengthwise direction and which portion is provided with an aperture, comprising in combination 1. two or more stacking bins spaced apart along, and

located below, said path to receive said articles;

2. means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced along said path and whose top surfaces define said path;

b. a diverter located ahead of each stacking bin and in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two adjacent tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto,

c. means for selectively moving each of said diverters between its inoperative and operative positions,

3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative position and until the trailing edge of a diverted article passed the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position;

4. a spindle extending upwardly from the bottom of at least one of said stacking bins of a shape and size to pass through the aperture in the limp end portion of said articles as they are dropped into said bin to control the stacking of said articles; and

5. end portion supporting means above said spindle movable between an operative position, wherein it will horizontally support the end portion of an article fed into the bin until the trailing edge enters the bin, and the aperture in the end portion of the article is in vertical alignment with said spindle, and an inoperative position, wherein it moves from beneath the end portion of the article to allow it to drop into the bin in a substantially horizontal condition so that the aperture therein will engage said spindle.

ll. Apparatus for stacking a series of sheet-like articles, which vary in density lengthwise thereof and include an end portion which is quite limp in the lengthwise direction and is provided with an aperture, selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation comprising in combination,

1. two or more stacking bins spaced apart along, and

located below, said path to receive said articles;

2. support means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path,

b. a diverter located ahead of each bin and in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two spaced tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto and support said article while it is being diverted and until it is directly above said stacking bin;

c. means for selectively moving each of said diverters between their inoperative and operative positions;

3. means for positively engaging and moving the articles individually throughout their entire path when said diverters are in their inoperative position and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position;

. at least one of said stacking bins having a spindle extending vertically upward from the bottom thereof of a shape and size to pass through the aperture in said articles as they are dropped into said bin to control the stacking thereof; and

5. means located between the top of said stacking bins and the top of said spindle for collecting a plurality of said articles and supporting them in flatwise stacked relation with the aperture thereon in vertical alignment with the top of said spindle and then dropping them as a group to facilitate directing the aperture in said articles over said spindle.

12. A stacking apparatus as defined in claim 11, wherein said article collecting means comprises blade members movable relative to opposite walls of said bin between an operative position, wherein the e ttend into the bin to enga e the underside of an article ed into the bin and limit its fa l into the bin, and an inoperative position, wherein they are withdrawn from said bin to release any articles supported thereby; and means for simultaneously moving said blade members between their inoperative and operative positions. 

1. Apparatus for stacking a series of sheet-like articles selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation comprising in combination,
 1. two or more stacking bins spaced apart along, and located below, said path to receive said articles;
 2. support means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path; b. a diverter located ahead of each stacking bin and in the spaCe between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two adjacent tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto; c. means for selectively moving each of said diverters between their inoperative and operative positions;
 3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative positions and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position, and including a. a plurality of pusher fingers; b. means for moving said pusher fingers in succession behind, and in substantially perpendicular relation to, the trailing edge of successive articles as they enter said path and moving them along said path to push the article across said support means; and c. means for successively lowering and raising said pusher fingers relative to the article engaged thereby as they approach and reach, respectively, a stacking bin to maintain said pusher fingers in pushing engagement with said article up to the time it is deposited in said stacking bin or is moved along said path across said stacking bin.
 2. support means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path; b. a diverter located ahead of each stacking bin and in the spaCe between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two adjacent tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto; c. means for selectively moving each of said diverters between their inoperative and operative positions;
 2. Stacking apparatus as defined in claim 1, wherein said means for moving said pusher fingers comprises a driven endless conveyor one reach of which is above and substantially parallel to said path and moves in an article-feeding direction relative to said path; means for maintaining said pusher fingers in spaced relation along said conveyor so that as said pusher fingers enter and pass along said one reach of the endless conveyor successive ones thereof move in succession in behind the trailing edge of successive articles as they enter said path and push the articles along said path, and wherein said means for successively lowering and raising said pusher fingers comprises guide means in said one reach of the conveyor for directing that portion of the conveyor approaching a stacking bin downward in a direction substantially parallel to the diverter when in its operative position and quickly raising said conveyor at the point in said one reach where a pushing finger reaches the trailing edge of a stacking bin.
 2. support means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path; b. a diverter located ahead of each stacking bin in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two spaced tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto; c. means for selectively moving each of said diverters between their inoperative and operative positions;
 2. means for supporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced along said path and whose top surfaces define said path; b. a diverter located ahead of each stacking bin and in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two adjacent tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto, c. means for selectively moving each of said diverters between its inoperative and operative positions,
 2. support means for sUpporting said articles in a flatwise condition as they are moved along said path and selectively diverting them into alternate ones of said stacking bins, and including a. substantially flat, stationary tables spaced apart along said path and whose top surfaces define said path, b. a diverter located ahead of each bin and in the space between two adjacent tables and arranged to move between an inoperative position, wherein it spans the gap between two spaced tables and forms a part of said path, and an operative position, wherein it is inclined downwardly from said path to divert an article moving along said path into a stacking bin immediately adjacent thereto and support said article while it is being diverted and until it is directly above said stacking bin; c. means for selectively moving each of said diverters between their inoperative and operative positions;
 3. means for positively engaging and moving the articles individually throughout their entire path when said diverters are in their inoperative position and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position;
 3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative position and until the trailing edge of a diverted article passed the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position;
 3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative position and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position; and
 3. Stacking apparatus as defined in claim 2, wherein said means for mounting said pusher fingers along said conveyor comprises a plurality of rods rotatably mounted at spaced points along said conveyor with their axis extending transversely of and substantially parallel to said path, one or more of said pusher fingers fixed to each rod to extend substantially at right angles to the axis thereof, a cam follower fixed to and extending at right angles from each of said rods, and an endless stationary cam path substantially concentric to said endless conveyor and engaged by a portion of said cam follower to rotatably position said rods so that the pusher fingers connected thereto remain at substantially right angles to, and project away from, the conveyor throughout the path of travel of said conveyor, that portion of said cam path controlling the pivotal movement of said rods as they move along said one reach of the conveyor so shaped that it maintains said pusher fingers substantially perpendicular to an article engaged thereby as the pusher fingers move up and down relative to an engaged article as dictated by said guide means for the conveyor.
 3. means for positively engaging and moving the articles individually throughout said entire path when said diverters are in their inoperative positions and until the trailing edge of a diverted article passes the trailing edge of the stacking bin to which it is diverted when one of said diverters is moved to its operative position, and including a. a plurality of pusher fingers; b. means for moving said pusher fingers in succession behind, and in substantially perpendicular relation to, the trailing edge of successive articles as they enter said path and moving them along said path to push the article across said support means; and c. means for successively lowering and raising said pusher fingers relative to the article engaged thereby as they approach and reach, respectively, a stacking bin to maintain said pusher fingers in pushing engagement with said article up to the time it is deposited in said stacking bin or is moved along said path across said stacking bin.
 4. A stacking apparatus as defined in claim 3, including article hold-down means connected with said rods for engaging the top of an article to hold it down as it is being pushed along said path by said fingers.
 4. article-supporting means associated with at least one of said stacking bins and movable in synchronism with the article moving means between an operative position, wherein it will horizontally support an article fed into said bin from the time the leading edge of the article enters the bin until the trailing edge enters the bin, and an inoperative position, wherein it moves from beneath an article fed into the bin to allow the article to drop down into the bin in a substantially horizontal condition; said last mentioned means comprising a plurality of blades symmetrically arranged to rotate about a vertical axis beyond the leading edge of the associated bin and in a plane immediately below the path of an article entering said bin, each of said blades providing an arcuate, substantially horizontal support surface for an article entering said bin from the time it enters the bin and until its trailing edge enters the bin at which time it passes from beneath the article to allow it to drop into the bin.
 4. a spindle extending upwardly from the bottom of at least one of said stacking bins of a shape and size to pass through the aperture in the limp end portion of said articles as they are dropped into said bin to control the stacking of said articles; and
 4. at least one of said stacking bins having a spindle extending vertically upward from the bottom thereof of a shape and size to pass through the aperture in said articles as they are dropped into said bin to control the stacking thereof; and
 5. means located between the top of said stacking bins and the top of said spindle for collecting a plurality of said articles and supporting them in flatwise stacked relation with the aperture thereon in vertical alignment with the top of said spindle and then dropping them as a group to facilitate directing the aperture in said articles over said spindle.
 5. end portion supporting means above said spindle movable between an operative position, wherein it will horizontally support the end portion of an article fed into the bin until the trailing edge enters the bin, and the aperture in the end portion of the article is in vertical alignment with said spindle, and an inoperative position, wherein it moves from beneath the end portion of the article to allow it to drop into the bin in a substantially horizontal condition so that the aperture therein will engage said spindle.
 5. A stacking apparatus as defined in claim 1, including an article-supporting member associated with at least one of said stacking bins and movable in synchronism with tHe movement of said pusher fingers between an operative position, wherein it will provide a substantially horizontal support for an article fed into said bin from the time the leading edge of the article enters the bin and engages said article supporting member until the trailing edge of the article enters the bin, and an inoperative position, wherein it moves from beneath an article fed into the bin and supported thereby to allow the article to drop down into the bin in a substantially horizontal condition.
 6. A stacking apparatus as defined in claim 1, wherein said article-supporting means comprises a disc rotatable about a vertical axis beyond the leading edge of the bin it is associated with and in a plane immediately below the path of entrance of an article entering said bin, said disc cut away to provide at least one arcuate horizontal support surface for an article entering said bin from the time it enters the bin and until its trailing edge enters the bin and at which time it passes from beneath the article to allow it to drop into the bin.
 7. Apparatus for stacking a series of sheet-like articles selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation comprising in combination,
 8. A stacking apparatus as defined in claim 7 in which the leading portion of each blade is bent to form a descending spiral beneath which the article freed from the preceding blade must fall.
 9. A stacking apparatus as defined in claim 7, wherein said sheet-like articles to be stacked vary in density lengthwise thereof and include an end portion which is quite limp in the lengthwise direction and is not supported by said artiCle-supporting means; and including an end portion supporting means movable between an operative position, wherein it will horizontally support the end portion of an article fed into said bin from the time the leading end thereof enters the bin until the trailing edge enters the bin, and an inoperative position, wherein it moves from beneath the end portion of an article fed into the bin to allow it to drop into the bin in a substantially horizontal condition; and means for moving said end portion supporting means between its operative and inoperative positions in synchronism with the movement of said article supporting means between its operative and inoperative positions so that said end portion will be supported in substantially the same plane as the remainder of the article as the article is fed into a bin and will be released at the same time as the remainder of the article is released by said article-supporting means to cause the entire article to drop down into the bin in a substantially horizontal condition.
 10. Apparatus for stacking a series of sheet-like articles selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation, said sheet-like articles varying in density lengthwise thereof and including an end portion which is quite limp in the lengthwise direction and which portion is provided with an aperture, comprising in combination
 11. Apparatus for stacking a series of sheet-like articles, which vary in density lengthwise thereof and include an end portion which is quite limp in the lengthwise direction and is provided with an aperture, selectively into two or more groups spaced along a given path to and over which the articles are fed in spaced-apart relation comprising in combination,
 12. A stacking apparatus as defined in claim 11, wherein said article collecting means comprises blade members movable relative to opposite walls of said bin between an operative position, wherein they extend into the bin to engage the underside of an article fed into the bin and limit its fall into the bin, and an inoperative position, wherein they are withdrawn from said bin to release any articles supported thereby; and means for simultaneously moving said blade members between their inoperative and operative positions. 